trivial: Do not recover the pending update if the boot time is unchanged
trivial: Do not recover the pending update if the boot time is unchanged

This ensures we can restart the fwupd service without marking updates that need
a reboot as failed.

hughsie/fwupd,superm1/fwupd,hughsie/fwupd,fwupd/fwupd,superm1/fwupd,superm1/fwupd,fwupd/fwupd,vathpela/fwupd,hughsie/fwupd,hughsie/fwupd,vathpela/fwupd,fwupd/fwupd,vathpela/fwupd,vathpela/fwupd,fwupd/fwupd